WIKIPEDIA, AARON GUSTAFSONThe age—and, therefore, size—of salmon when they mature is controlled by the same gene in males and females, but acts differently in the sexes, scientists reported today (November 5) in Nature. VGLL3 promotes earlier maturation in males and later maturation in females.
The study describes how a single gene can drive sex differences in the optimal form of a trait, in this case, smaller size at maturity for males and larger size for females. “Since different forms of the gene are favored in males and females, natural selection favors both forms being maintained in the population. This leads to the variation in age at maturity being maintained, which promotes the stability and resilience of Atlantic salmon populations,” Jaakko Erkinaro, a coauthor from the Natural Resources Institute Finland, said in a statement.
Examining genetic information from 1,500 salmon, the researchers found two variants of VGLL3, one for early maturity and one for later maturity. Heterozygote fish ended up expressing the phenotype that was most optimal for its sex. ...
